What is the BMR for a 18-year-old man?

The estimated BMR (basal metabolic rate) for a 18-year-old man of average height and weight is 1899 kcal/day, calculated using the Mifflin-St Jeor equation.

Calorie Guide · Age 18

Calories for a 18-Year-Old Man

Q: How many calories does a 18-year-old man need?

A lightly active 18-year-old man of average weight and height needs approximately 2611 kcal/day to maintain weight. Sedentary needs are around 2278 kcal, and very active around 3275 kcal.

Q: How many calories should a 18-year-old man eat to lose weight?

A 18-year-old man should eat approximately 2111 kcal/day to lose about 0.5 kg (1 lb) per week. This is a 500 kcal deficit from the estimated maintenance of 2611 kcal.

BMR, TDEE and exact calorie targets for weight loss, maintenance and muscle gain at age 18.

Calorie Needs at Age 18 — Average Man

1899

BMR (at rest)

2278

Sedentary TDEE

2611
Lightly active TDEE

2943

Moderately active

2111

Weight loss target

2611

Maintenance

2911

Muscle gain target

How Many Calories Does a 18-Year-Old Man Need?

Using the Mifflin-St Jeor equation with average US height and weight for a man aged 18, the resting metabolic rate (BMR) is approximately 1899 kcal/day. With typical daily activity included, total calorie expenditure (TDEE) ranges from 2278 kcal (sedentary) to 3275 kcal (very active).

Age 18 note: Metabolism is at its peak in your late teens and early twenties. Prioritize protein and resistance training to build muscle that pays dividends for decades.

Calorie Targets by Goal

Goal	Daily Calories	Expected Result
🔵 Aggressive weight loss	1861 kcal	~0.75 kg/week
📉 Weight loss	2111 kcal	~0.5 kg/week
✅ Maintenance	2611 kcal	Weight stable
💪 Lean bulk	2911 kcal	~0.25 kg/week
🏋️ Aggressive bulk	3111 kcal	~0.5 kg/week

Calorie Needs by Activity Level

Activity Level	Description	Daily Calories
Sedentary	Desk job, minimal movement	2278 kcal
Lightly active	1–3 workouts/week	2611 kcal
Moderately active	3–5 workouts/week	2943 kcal
Very active	Hard training 6–7 days/week	3275 kcal

How Metabolism Changes Around Age 18

Metabolic rate declines approximately 1–2% per decade after age 30, driven primarily by muscle loss (sarcopenia) rather than any inherent slowdown. At age 18, your BMR of 1899 kcal reflects your current muscle mass, height and hormonal status. The single most effective way to maintain or raise your BMR is resistance training — each kilogram of lean muscle burns roughly 13 kcal/day at rest.

Age	Estimated BMR (man)	Change vs age 18
18	1899 kcal	—
18	1899 kcal	—
18	1899 kcal	—
23	1874 kcal	-25 kcal
28	1849 kcal	-50 kcal

Macronutrient Split at 2611 kcal

Macro	% of Calories	Grams/day	Calories
Protein	30%	196 g	784 kcal
Carbohydrates	40%	261 g	1044 kcal
Fat	30%	87 g	783 kcal

At age 18, protein intake is especially important. Aim for at least 71–89 g/day to maintain muscle mass, whether you're in a deficit, at maintenance, or in a surplus.

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Frequently Asked Questions

How many calories does a 18-year-old man need per day?A lightly active 18-year-old man of average size needs approximately 2611 kcal/day to maintain weight. This ranges from 2278 kcal (sedentary) to 3275 kcal (very active).

How many calories should a 18-year-old man eat to lose weight?Aim for 2111 kcal/day — a 500 kcal deficit from the 2611 kcal maintenance estimate — to lose approximately 0.5 kg per week. Never go below 1200 kcal (women) or 1500 kcal (men) for extended periods.

Does age 18 affect how many calories you burn?Yes. Every decade after 30, BMR drops ~1–2% mainly due to muscle loss. At age 18 the estimated BMR is 1899 kcal — compare to 1839 kcal at age 30. Resistance training largely offsets this decline.

Related Age Guides

Sources

WHO CDC Mifflin-St Jeor (PubMed)